The present study aimed to investigate the differences in human lumbar intradiscal pressure (IDP) characteristics during simulated spinal manipulation and spinal mobilization. A total of 12 adult fresh lumbar spinal specimens (T12‑S2) were randomly divided into two groups. The parameters of simulated spinal mobilization were as follows: Preload angle, 15˚ (speed, 3˚/sec); maximum angle, 20˚ (speed, 1˚/sec); and 9 N horizontal force to the L5 spinous process. The parameters of simulated spinal manipulation were as follows: Preload angle, 15˚ (speed, 3˚/sec); impulse angle, 20˚ (impulse speed, 33˚/sec) and 22 N horizontal force to the L5 spinous process. The maximal IDP during both techniques was greater than the initial and end pressures (P<0.01). There was no difference between the initial and end IDP (P>0.05). The maximal IDP on the rotating side was greater than that on the contralateral side during the two techniques (P<0.05). There was no difference in both initial and end IDPs between the two sides (P>0.05). There was no difference in the maximal IDP between the two techniques (P>0.05). The ascending speed of IDP during manipulation was faster than during mobilization (P<0.01), while there was no difference in the descending speed between the two techniques (P>0.05). The maximal IDP on the rotating side was greater than the contralateral side during simulated spinal mobilization and manipulation (P<0.05). The ascending speed of IDP was faster during manipulation than mobilization (P<0.01). Therefore, thrust manipulation may have more instant impact to discs than mobilization.